The present invention relates to an instrument for medical applications, and particularly to an instrument for endoscopic applications which includes a multi-part functional element (for example, end effectors or forceps jaws) and an operating unit for the operation of the functional element for effecting a surgical operation.
Endoscopic instruments such as forceps or pincers have become known wherein the jaws of the forceps is adapted to perform not only simple opening or closing movements, respectively, as this is the case with the forceps known from the document WO 94/20034. For an explanation of all details not described here in more details explicit reference is made, by the way, to that prior art document.
For instance, the most different instruments are known which present two or more functional elements on their distal end, which can be pivoted or displaced along the longitudinal axis of the instrument and which are adapted to perform mutually independent movements and, if necessary, movements linked up with each other.
Furthermore, instruments or forceps have become known wherein the jaws of the forceps present a multi-part configuration. In an exemplary manner reference should be made in this context to the German Patent DE 694 03 583 T2.
Moreover, manipulators with multi-part function elements for holding or spreading tissue etc. have become known from the Japanese Patent 06311984 A, the European Patent EP 0 688 538 A1 or the U.S. Pat. No. 5,549,636.
The functional elements in the known instruments are operated, as a rule, by scissors or pushing handles or by elements into which the operator can introduce his or her fingers. These elements translate the movement of the fingers into a movement of the distal functional elements. In this respect additional reference is made to the U.S. Pat. No. 5,630,831 or the European Patent EP 0 613 762 A1.
Additionally, handles with operating elements for several functions have become known.
The operating units so far used in prior art are, however, unsatisfactory from an ergonomic point of view, especially when more than one distal functional element must be operated. Furthermore, the known operating units are not intuitive. The movement which the operator is required to perform on the operating element frequently hardly resembles the movement to be performed by the corresponding functional element in terms of direction and kind of movement.
Under certain conditions this may result in serious errors in operation of these instruments in the course of a surgical operation.
The present invention is based on the problem of simplifying the operation of instruments, particularly those including a plurality of functional elements, in such a way that an intuitive, simple and safe operation will be possible.
One inventive solution to this problem is defined in Patent claim 1. Improvements of the invention are the subject matters of the dependent claims.
In accordance with the present invention, the operating unit is so configured that it can be grasped by one hand, and comprises at least two circumferential elements (e.g., at least two pivotable and/or tiltable elements) which are components of the surface of the operating unit and which, by their movement, control each one part of the multi-part functional element. It is particularly preferable that the operating unit is so configured that it serves also as handle for holding the instrument.
The operator can thus hold the instrument with one hand only and control, at the same time, the distally disposed functional elements by moving individual fingers or finger joints, respectively. Grasping is furthermore facilitated it the elements are configured, at least approximately, as segments of a rotational body such as a cylinder or a sphere.
In any case, the inventive configuration presents the particular advantage that the operator can grasp the operating unit by his or her complete hand, with the rear part bearing against the thenar region and is fixed thereby. One pressure by the thenar against the rear end may serve to move the functional elements as a single unit, i. e. jointly.
Another ergonomic improvement is achieved when gripping depressions are provided for the fingers. This provision supports the intuitive operation in particular.
From an ergonomic point of view it is particularly expedient to provide two elements coupled to each other, which are adapted for being tilted in different directions for moving the individual parts of the functional elements. The elements are preferably connected to via linkages to sliding elements which, in their turn, are connected to rods moving the functional elements on the distal end.
In an alternative embodiment of the invention four segments may be provided whereof two respective ones are coupled to each other. The mutually coupled segments are arranged symmetrically relative to a plane including the longitudinal axis of the connecting element.
Due to the mutually coupled segments, which are formed symmetrically relative to a plane including the longitudinal axis of the connecting element, a symmetrical operation free of a tilting momentum is achieved for the functional elements provided on the distal end.
Both designs may be used to operate one or several functional elements.
It is possible to articulate the segments provided on the proximal side to a stationary part of the instrument and to couple it via a pushing bar to a sliding element connected to the second connecting rod. The segments disposed on the distal side are then articulated on the segments provided on the proximal side and coupled via a pushing rod to a sliding element, which is connected to the first connecting rod.
It is moreover advantageous to bias the operating elements into a position in which the functional elements take a defined position. In the event of functional elements configured as jaws of forceps it is then preferable that the defined position is that position in which the forceps jaws are open.
Independently of the particular configuration of the instrument or the forceps, respectively, it is preferable that the operating elements are biased into a position in which the functional or jaw elements, respectively, take a defined position also under the aspect set out below, because in such a case the operator working with the instrument can always change the instrument into an initial or basic position when the operating unit is released. This xe2x80x9cinitial positionxe2x80x9d may be that position, for instance, in which the two parts of each jaw element are open.
It is moreover expedient to provide locking elements by means of which the parts of each functional or jaw element, respectively, can be locked in a defined position. With these provisions the operator can lock the instrument in a position which is advantageous or ergonomically expedient for the respective surgical or examination operation.
It is furthermore advantageous to make provisions for a rotation of the connecting element and hence of the functional or jaw element disposed on its distal end about its longitudinal axis, such as this is known, for example, from the document WO 94/20034. It is possible to provide a wheel on the connecting element for rotation of the distal end, which wheel when operated rotates the connecting element. In this design various catch positions may be provided.
The inventive solutions apply to both rigid and flexible instruments.
If the multi-part functional elements are multi-part forceps they may have, of course, also the function of scissors or a cutting function, in addition to a mere forceps function. To this end all the known forms of jaws may be employed; even a roughening of the surface may be provided in order to prevent a lateral deflection of the object.
Claims 22-31 define a multi-part forceps device as an example of a multi-part functional element, wherein each mobile jaw element consists of two parts whereof one part, i.e. the part on the proximal side, is articulated on the connecting element whilst the other part, i.e. the part on the distal side, is articulated on the proximal part directly or via a lever mechanism. The parts of the two jaw elements on the proximal side and the parts of the two jaw elements on the distal side are movable independently of each other. With this provision it is possible that the operator is able to pivot the two jaw elements not only as a single unit but can bend them also in a manner similar to the joint of a finger. With this design it is possible, for instance, to grasp a bundle or tract of tissue by xe2x80x9cgrasping around itxe2x80x9d rather than only on one side in a xe2x80x9csqueezingxe2x80x9d manner. Hence sensitive, and even fairly large objects can be grasped carefully and reliably and yet the forceps jaws may be approached to a very small diameter.
It should be emphasised here, however, expressis verbis, that the most different functional elements, which need not at all be restricted to forceps or scissors but can be designed in any form whatsoeverxe2x80x94as is known from prior artxe2x80x94may, of course, be controlled with the operating unit configured in accordance with the present invention.